The supermarket chain pleaded guilty to three breaches of the Food Safety and Hygiene (England) Regulations 2013 after inspectors found the dead vermin alongside mouse droppings and pupae shells at its distribution centre in Enfield, north London that distributes food to online shoppers across London and Essex.

While there is nothing to suggest the poor standards are indicative of Asda’s nationwide operation, they are nevertheless alarming for customers of the popular supermarket chain.

Spilt foodstuffs, rotting coriander and gnawed cereal and sugar packets were also discovered. Asda, a subsidiary of the US retail giant Walmart, was also ordered to pay costs of £4,843.61 to Enfield council.

“It beggars belief that a national retailer would allow food to be stored in an environment where rodents are running riot,” Daniel Anderson, the council’s cabinet member for environment said.

“It is simply unacceptable for customers to be exposed to the potential risk of harm because a company cannot get its house in order and store foodstuff in a safe and hygienic manner. I am therefore pleased that magistrates have taken a tough stance and issued a heavy penalty.

“Hopefully, it will send out a strong message to all retailers that we will not tolerate them being less than properly vigilant and ensuring their staff abide by their own stated hygiene policies to protect the health and wellbeing of their customers.”

The fine was handed down by the courts almost a year after food safety inspectors visited the depot.

The dead mice and flies were discovered in the bread section, mouse droppings on shelves and the gnawed cereal and sugar packets in the home baking aisle when the site was inspected on 27 May last year.

An Asda spokesperson said in a statement that the company was “deeply sorry” for the “completely unacceptable” standards at Enfield.

“On this occasion the strict processes we have in place failed at a local level,” the statement said. “We would like to reassure all our customers that immediate steps were taken as soon as the issue was flagged last year to restore the high standards that our customers expect from us.”